A surgical instrument comprises a shaft, an end effector extending distally from the shaft, and a housing extending proximally from the shaft. The housing comprises a first shroud portion, a second shroud portion, a working assembly nested in the first shroud portion, wherein the working assembly is detachable from the first shroud portion, wherein the second shroud portion is removably couplable to the first shroud portion to permit the working assembly to be detached from the first shroud portion, and at least one securing member movable to secure the working assembly to the first shroud portion.